BNB Smart Chain (BSC) activated its Pasteur hard fork on Tuesday, closing bridge verification and validator authorization gaps while introducing a new block-building route intended to increase transaction throughput per block.
The upgrade combines three BNB Evolution Proposals. BEP-682 rejects duplicate validator entries during cross-chain light-block verification. BEP-695 tightens controls on validator key rotation, slashing, and governance voting. BEP-675 changes how specialist builders submit blocks to validators, allowing them to submit pre-executed blocks that validators verify against consensus rules, sign, and broadcast before completing full execution verification afterward.
Block-Building Efficiency Gains
The previous block-building route required builders to execute transactions before submission and validators to execute again before signing, consuming time within BSC’s 450-millisecond block window. BEP-675 eliminates the redundant execution step.
Tests on QANet, an internal environment designed to mirror BSC’s geographically distributed validators, showed an 88% throughput increase from the new block-building route. Before BEP-675, QANet recorded 1,237 transactions per second; after implementation, throughput reached 2,324 transactions per second. Average gas used per block increased from 46.35 million to 84.15 million, while the gas limit remained at 100 million.
BNB Chain cautioned that test figures were from controlled workload and did not represent mainnet measurements.
Broader Network Evolution
Pasteur follows earlier BSC upgrades designed to reduce block time. The Maxwell hard fork in June 2025 reduced average block time from 1.5 seconds to 0.8 seconds. A subsequent Fermi upgrade reduced block time further to 450 milliseconds.
The Pasteur activation marks the latest in a series of network improvements targeting both security and transaction capacity on BSC.
